Posted online April 21, 2008, on www.jco.org.

In the first study to assess mammography in women 80 and older, researchers found that having regular mammograms significantly decreases the risk of being diagnosed with late-stage breast cancer, but only about one-fifth of women in this age group receive them regularly. The study, which was published in the Journal of Clinical Oncology, also showed that each mammogram that was performed in these older women was associated with a further reduction in the risk of being diagnosed with late-stage disease.

The American Cancer Society recommends annual mammography beginning at age 40, with no upper age limit for women in good health. However, many older women aren’t following those guidelines. Real-world experience has shown that women are less likely to get regular mammograms as they age, especially if they have medical conditions that are likely to limit their life expectancy.

Using Medicare data for the years 1996 to 2002, researchers examined mammography use in the five-year period before breast cancer diagnosis among 12,358 women age 80 and older. Those who had no mammograms during that period were considered nonusers; irregular users had one to two mammograms and regular users had three or more mammograms.

They found that only 22 percent of women were regular users of mammography, 29 percent were irregular users and 49 percent had no mammograms in the five years before their diagnosis. Regular users were more likely to be diagnosed with stage I disease, while stage II-IV breast cancers were more commonly found among the nonusers and irregular users.

Five-year survival from breast cancer was greatest among regular users (94 percent) and lower among irregular users (88 percent) and nonusers (82 percent). However, the researchers cautioned against linking mammography use to better survival, because survival from diseases other than breast cancer was also better among women who had regular mammography (80 percent) compared with irregular users (69 percent) and nonusers (59 percent)—suggesting that regular users may be in a better state of health compared with women who don’t undergo regular mammography.

What This Means for Patients

Mammography has been shown to be an excellent means of detecting breast cancer early, when it is most likely to be cured. This study suggests that mammography benefits may have no age limit and that older women should consider being screened on a regular basis, generally every 1-2 years. Older women—particularly those in reasonably good health—should discuss the benefits of mammography with their healthcare providers.

Helpful Links

Cancer.Net Guide to Breast Cancer

Feature on Mammography: What to Expect